<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        *{
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        main{
           position: relative;
           width: 100%;
           height: 100vh;
           overflow: hidden;
        }
        main video{
            width: 100%;
        }
        .cover{
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-color: #000;
            transform: scale(20);
            mix-blend-mode: multiply;
        }
        .cover::before{
            content: '';
            position: absolute;
            left: 50%;
            top: 50%;
            width: 80px;
            height: 300px;
            transform: translate(-50%,-50%) skew(45deg);
            background-color: #fff;
        }
        .cover::after{
            content: '';
            position: absolute;
            left: 50%;
            top: 50%;
            width: 80px;
            height: 300px;
            transform: translate(-50%,-50%) skew(-45deg);
            background-color: #fff;
        }
    </style>
</head>
<body>
    <main>
       <video src="video/11.mp4" autoplay loop muted></video>
       <div class="cover"></div>
    </main>
    <script>
        let cover = document.querySelector('.cover');
        let scale = 20;

        let bian = setInterval(function(){
              
               scale = scale - 0.05;

              cover.style.cssText = `transform: scale(${scale});`

              if(scale<=1)
              {
                  clearInterval(bian);
              }

        },20) 

    </script>
</body>
</html>